We have previously demonstrated in our laboratory that several rhodium(II) carboxylates produce significant tumor regression when given to mice with Ehrlich ascites tumors. The research project involves the synthesis of a wide variety of rhodium(II) complexes and the testing of these compounds for anticancer activity. The nature of the bonding and the thermodynamic and kinetic stability of the complexes formed between the rhodium(II) carboxylates and molecules of biologic importance is also being investigated. In order to determine the mechanism of action of these complexes, enzyme inhibition studies are being carried out on several systems. BIBLIOGRAPHIC REFERENCES: J.L. Bear, H.B. Gray, Jr., L. Rainen, I.M. Chang, R. Howard, G. Serio, and A.P. Kimball, Interaction of Rhodium(II) Carboxylates with Molecules of Biologic Importance, Cancer Chemother. Rep. 59, 611-620 (1975). L. Rainen, R.A. Howard, A.P. Kimball, and J.L. Bear, Complexes of Rhodium(II) Carboxylates with Adenosine 5'-Mono-, 5'-Di-, and 5'-Triphosphates, Inorg. Chem. 14, 2752-2754 (1975).